The results of the tests on Hingis are due next week and whatever the outcome her manager Mario Widmer said she will be "80 per cent" likely to miss the French Open Roland Garros, which starts in 12 days. He said: "We want to resolve this once and for all. Only one week of
training before Roland Garros is not enough."
The French Open is the only Grand Slam Hingis has yet to capture. World number one Venus Williams could join Hingis on the sidelines at Roland Garros, suffering from a wrist injury.
Hingis played her first competition at four. By 14 she joined the professional circuit. In 1996 she made Wimbledon history by becoming the youngest player to win a championship event, the ladies doubles. A year later she won the singles title. She has earned almost £13million during her career.
